Sash-center.



R. KJBLLLN & E. ANDERSON.

SASH CENTER.

APPLIOATION FILED AUG. 24, 190e.

Patented Dec. 22, 1908;

UNITED STATES PATENT OFFIOE.

SASH-CENTER.

Specification of Letters Patent.

Patented Dec. 22, 190s.

Application filed August 24:, 1908. Serial No. 449,902.

To all whom it may concern:

Be it known that we, RUDOLPH KJELLIN and ERIC ANDERSON, citizens of theUnited States, residing at Buffalo, in the county of Erie and State ofNew York, have invented a new and useful Improvement in Sash-Oenters, ofwhich the following is a speciiication.

This invention relates to a sashecenter or pivot-fixture for swingingtransoms and other sashes, the same belonging to devices of this classwhich retain the sash in a more or less open position.

The object of our invention is the provision of a reliable sash-centerand holder oi this character which is comparatively simple andinexpensive in construction.

In the accompanying drawings: Figure 1 is a sectional `face view of awindow frame and sash provided with the improved center. Figs. 2 and 3are perspective views, respectively, of the pivot-plates.

Similar letters ci' reference indicate corresponding parts in theseveral figures.

The invention is equally applicable to vertically andhorizontally-swinging sash, the same being shown in connection with avertically-swinging sash in the drawings, in which A indicates the sashand B the stationary window Jframe.

C and D represent a pair of plates secured respectively to the edge oithe sash and the opposing edge of the window frame and countersunktherein, as shown.

E is a pivot or bolt passing centrally through these plates andconnecting them. One of the plates, say D, is preferably provided on itsface concentrically with the plivot bolt with a circular boss f which istted in a corresponding recess g in the face of the opposing plate C.This boss and recess increase the pivotal bearing surface of' the plateson each other and largely relieve the connecting bolt E from strain. Ifdesired, a hub h may be formed on the recessed plate C around thepivot-bolt, which hub is htted in a cylindrical cavity i arrangedcentrally in the boss f. This hub and cavity are however notindispensable, and may be omitted if desired.

Formed in the bottom of the recess concentrically with the hub 72, is acircular row of detent-depressions j with which interlock one or moredetent balls 7c or equivalent members carried by the plate D. Theseballs are guided in sockets l formed in the face of the boss f oppositethe row of depressions y', and are backed by spiral or other suitablesprings m seated in said sockets and tending to constantly press theballs into said depressions. The latter are preferably concave to fitthe projecting portions of the detent balls, as shown. In the drawingsfour equidistant balls are shown, but a greater or less number may beemployed, if desired.

By this construction, the detent-balls interlock with the correspondingset of depressions in all positions of the sash and reliably hold it atany angle to which it may be turned lor o ening it more or less. At thesame time, tlie engagement of the balls with the depressions, thoughsufficiently reliable to hold the sash in place, is frictional ratherthan positive and therefore permits the sash to be easily swung from oneposition to another.

We claim as our invention:-

l. A sash-center comprising a pair of plates adapted to be securedrespectively to the sash and the trame, a pivot connecting said plates,one of the plates having in its inner face a row of detent-depressionsarranged concentrically with said pivot and the other plate having inits opposing inner face one or more sockets, and spring-presseddetent-members seated in said sockets and adapted to interlock with saiddepressions.

2. A sash-center comprising a pair of plates adapted to be securedrespectively to the sash and the frame, a pivot passing through saidplates, one of the plates being provided in its face with a circular rowof depressions arranged concentrically with the pivot and the otherplate being provided in its face with a socket, and a spring-pressedball arranged in said socket and adapted to interlock with saiddepressions.

3. A sash-center comprising a pair of plates adapted to be securedrespectively to the sash and the frame, a pivot passing through saidplates, one of the plates having in its face a circular recess providedin its bottom with an annular row of depressions, and the other platehaving a circular boss seated in said recess and provided in its facewith sockets arranged opposite said depressions, and spring-presseddetent-members arranged in said sockets and coperating with saiddepressions.

4. A sashecenter comprising a pair of plates adapted 'to be securedrespectively to the sash and the frame, a pivot passing bers seated inVsaid socket and interlocking through said plates, one of the plateshaving With said depressions. in its face a circular recess providedcentrally Witness our hands this 21st day of August,

with a hub through which the pivot passes 1908. 5 and around said hubwith an annular roW of 'l depressions, and the other plate having acircular boss fitted in said. recess and provided centrally with acylindrical cavity which re- Witnesses:

ceives said hub and around said cavity with C. F. GEYER,

10 sockets, and spring-pressed detent-niem- E. M. GRAHAM.

